Find any 657- phone number in California

The 657 area code is a telephone numbering plan code (NPA 657), introduced in 2018, which is used to designate the southern part of the Inland Empire in California. This area consists of Riverside and San Bernardino counties. 657 is the most recently added California area code and currently has the second smallest population of any California area code (behind 564).

Area codes are the first three digits of a 10-digit North American Numbering Plan telephone number. These codes are issued by the North American Numbering Plan Administrator (NANPA). NANPA assigns area codes in order to allow millions of unique 10-digit telephone numbers to be issued throughout North America. The NANPA assigns area codes based on population and geography, and area code assignments may be changed as populations in a particular geographic region grow or shrink.